This circuit, found in a 1964 US documentation, consists of a selective amplifier that lets only 10 Hz pass around a 400 Hz center frequency with the indicated components.
This vox was found in Hughes documentation from 1968. The circuit uses components from the era. A...
This circuit is from Mullard documentation from 1969. Transistors support current equivalents. Output...
September 2017 - Microchip's MCP6411 operational amplifiers for frequencies up to 1 MHz are in...